The use of throw-away hypodermic needles and syringes has become common practice in modern day health care facilities, primarily because the pre-packaged syringes and needles are reliably sterile, convenient to use and eliminate the relatively hazardous and difficult task of sterilizing needles and syringes for re-use.
Despite the apparent desirability and convenience of such throwaway devices, safe disposal of used contaminated needles and syringes presents major economic and safety problems. Incineration of used syringes and needles immediately after use is obviously desirable, but not easily achieved. Bulk disposal of accumulated needle/syringes either by burning, burial or other means is not only expensive, but unsafe, particularly where contaminating substances remain present in the hollow hypodermic needles and syringe bodies. Mechanical severing or breakage of the needles while avoiding their immediate reuse fails to eliminate hazardous and dangerous contaminating fluids and residue whereby accidental engagement of a sharp contaminated needle part becomes a realistic hazard.
It is well known that electrical metal conductors having a relatively low volume to surface area, may be incinerated by electrical resistance heating if subjected to heavy electrical currents even for short time periods. Hollow metal syringe needles and/or dialysis fistulae are good examples of such conductors, and thus are ready candidates for destruction by electrical incineration.
Electrical needle destruction devices employing the incineration effect are known in the prior art as exemplified by U.S. Pat. No. 4,628,169, for example, wherein an end portion of a needle held in a syringe is inserted between a pair of stationary electrodes causing a short circuit to melt the outer end of the needle, leaving an extensive portion of the needle on the needle head. Separator means are provided for detaching the needle head from the syringe.
In a later development set out in U.S. Pat. No. 4,877,934, a syringe held needle is inserted into a slide track to engage a pair of vertically spaced electrodes. The lower electrode angularly converges with the upper electrode and engages the lower end of the needle. By manually moving the needle and syringe toward the inclined electrode, the needle is progressively burned away and disintegrated.
In a more recent U.S. Pat. No. 5,212,362, a needle destroyer employing electrical incineration is set out in which a syringe held needle is inserted into a socket in a housing so that the needle engages a stationary grounding electrode. An electrically active electrode is then pivotally moved onto the needle creating an arc to progressively volatilize or disintegrate the needle.
While the prior art exemplified by the above noted patents provide needle destroying devices designed for on sight use, the use of manually controlled destruction cycles and needle or electrode movements does not ordinarily provide sufficient heating of the needle away from the immediate severance zone to sterilize the needle or syringe of possible bio-hazardous liquids and residue.